As far as shells/choke, most of the after-market tubes will give you good performance. And it seems that Winchester HV shells will pattern well in most guns. The tighter the choke, the smaller the shot that'll shoot well through it.
As to using a vest, its like using a scope on your deer rifle. Yes, you don't need it, but once you get it, you wonder why you hunted without one. Sitting on the cold, damp ground for a couple of hours without a pad is no fun. Besides, in the off-season, it's my storage container. All my turkey hunting stuff resides in my vest. Come spring, I throw in a couple of shells and go.